Add detiling option to the shader

[TokisanGames]

The current rotation used for detiling is very unattractive for strong patterns like rock, and it is questionable for weak patterns like grass/mud. One user mentioned rotation messes up normals.

I think we should differentiate between detiling and rotation and make these changes:

• (This Issue) Include a better detiling algorithm, such as one of these from IQ, or one from hterrain. Either are superior to the current implementation.

• (Separate issue) Include paintable rotation in our control map so we can manually paint rotated textures like cobblestone paths and orient them properly.

See proposed control map #64 (comment)
Related to #97
This should also address #69

[outobugi]

We probably can change the de-tiling but it will be a lot slower than our current one. Our method utilizes the index blending and the de-tiling is basically free. Most de-tiling methods use noisy patterns and ours is a grid. We would need to check if neighboring indices are same, skip them and do the de-tiling. See updated #64

[Xtarsia]

Godot_v4.3-dev5_win64_b1fMAhZ0Ee.mp4

Along side Per Texture, UV Scale & UV Rotation;
a UV Rotation Blend value would be very handy. (some textures need hardly any at all, making de-tiling almost free for those cases)

Currently as implemented the performance hit to enable de-tiling is between 5-15% increase in sample reads.
The limit if setting blend to absolute maxium is 100% (double) but anything past 20% is kind of redundant.

and note 1 optimisation as im typing this: can disable when blend value is at maxium)

(some minor optimisations / refactoring to fit with the rest of the base shader aside)

[JekSun97]

We probably can change the de-tiling but it will be a lot slower than our current one. Our method utilizes the index blending and the de-tiling is basically free. Most de-tiling methods use noisy patterns and ours is a grid. We would need to check if neighboring indices are same, skip them and do the de-tiling. See updated #64

Please do not add anything that will worsen optimization

[TokisanGames]

This is already completed. See the end of this video. https://x.com/TokisanGames/status/1793957324069158955?t=xkVLzEQiI453cZVojmmBbA&s=19

[JekSun97]

This is already completed. See the end of this video. https://x.com/TokisanGames/status/1793957324069158955?t=xkVLzEQiI453cZVojmmBbA&s=19

Wow! it is excellent! As far as I know, this doesn't even exist in Unity.